UPS Advice

[VK2KRR]

Does anyone have knowledge of Uninteruptable Power Supplies (UPS)?

I know partically nothing about them except what they do.

I think I need to invest in one on my shack PC to cover 240V power failures, brown outs etc.

Any recommendations of type, size and where to source one from would be very helpfull.

Thanks

[VK6ADF]

Hi Leigh...I don't have any info re sources of a UPS but whoever is going to suggest anything will need to know how long you require power to be kept on. Generally UPS's are only a fairly short duration that are readily available at computer type shops.

I presume it's your AIS PC you leave running. My suggestion would be do like me and get a 12v PC and run it off a car battery/charger combination. Then when power goes off you have many hours of battery power.

[VK2KRR]

Hi Phil,
I guess as long as practicably possible. But even 1/2 hour to an hour would be good. Sometimes we get short drop outs which can be enough to drop the computer out, just mainly to cover those.

[VK6ADF]

Do a search on http://www.altronics.com.au for UPS and it might give you some idea's.
Your local computer shop should be able to get one if they don't have them in stock. Can also be found on eBay if you search for one, eg: Eaton Powerware. Don't know how good they are so do some research.

[VK4CZ]

Leigh

We obtained a Sola UPS 305 for free from a local business updating their computer equipment... for free as it had been written off the books! This provides only about 4 minute full load, 15 minutes low load of 'up time' post loss of power.

These types may not be suitable for your requirements, but it provides an indication of the availability and minimum price when asking! A quick search of FleaBay shows that you can get similar sized and larger UPS relatively cheap. Good luck!

[VK3DXE]

How much do you want to spend Leigh?

The cheapies will generally only give you enough power to safely shut down your system or take care of brownouts/short-term blackouts. One of the ones I have here at work will run 3 rackmount servers, 2 SANS and associated peripherals at full load for an hour, but that is #@$%ing expensive and just as heavy.

[VK4TI]

Hi Phil,
I guess as long as practicably possible. But even 1/2 hour to an hour would be good. Sometimes we get short drop outs which can be enough to drop the computer out, just mainly to cover those.

I run a very used 3.5kw sola ups with several deep cycle batteries I was given externally offering about 15>20 minutes of computing as needed and a vhf new that gear would be prohibitive

[VK6ZFG]

If one intends to extend the run time of a UPS by adding external batteries to a UPS not intended to have external batteries one needs to consider if:

1) the UPS is going to be able to handle the extended operation thermally?

2) the external batteries are at mains potential thus creating a dangerous situation?

73s

Igor
VK6ZFG

[VK5ZD]

Note that some of the cheaper UPS units will automatically shut off after 10 minutes or so regardless of the state of the battery. I suspect this is to stop the electronics overheating.
Just something to check if you want the device to run for at least 30 minutes.

73
Iain

[VK2KRR]

Thanks for the info guys. I wasn't aware of how long or short they ran for, obviously depending on the load.

Looks like it would be pretty expensive for anything to hold much longer than 10 mins.

[VK2JDS]

I suggest a 24volt battery bank, high frequency (chinese) 2kw inverter and a charger.

Here the whole house runs off this system. inverters are cheap these days unless you want a low frequency converter something like a selectronics. batteries you may be able to scrounge through your work from a decommisioned site etc, same with the charger or get a cheapy off ebay . or make a large linear charger from a cheap welder and rectifier set.
you can add solar panels later on if you get extended power outages.

out here when there is a storm the mains power can be off for half a day or more, and very expensive to connect (and ongoing bills) hence we didnt bother connecting to it opting to go fully solar off-grid with a 2kw system

at wyong we were offered a pair of 150ah huge batteries (near new) for virtually nothing but we couldnt fit them in the car, bought a 2kw true sinewave inverter (works fine) from J@ycar for $20 and a 125w panel.. i am sure you could find enough bits to make something up.

just needs a proper box outside for the batteries to allow gas venting safely.

[VK3ALB]

bought a 2kw true sinewave inverter (works fine) from J@ycar for $20

Any noise on HF/VHF/UHF?

[VK2KRR]

Hi David, you really have it sorted out well up there.

As Lou mentioned, my biggest worry would be extra radio interference. I'd hate to spend big dollars on a complete set up and find out its got noise issues.
I do have solar hot water here, but not the same as solar panels as such. The sun just heats the water. (Not that there has been sun for the past week or so!).

This is all giving me lots of ideas to think about, thank you.

[VK2JDS]

some noise on HF yes , but above 30 MHz its quiet. and thats without any shielding work

the noisiest part is the PWM regulator on the solar array when the battery bank goes into float